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Abstract:

A backlight unit according to the embodiment comprises an LED module
comprising an LED; a case supporting the LED module; a fixing part fixing
the LED module to the case; a reflective sheet comprising an opening for
exposing the LED on the LED module and the fixing part; and a guide pin
fixing the reflective sheet to the case.

Claims:

1. A backlight unit comprising:an LED module comprising an LED;a case
supporting the LED module;a fixing part fixing the LED module to the
case;a reflective sheet comprising an opening for exposing the LED on the
LED module and the fixing part; anda guide pin fixing the reflective
sheet to the case.

2. The backlight unit as claimed in claim 1, wherein the LED module
comprises a printed circuit board, the LED on the printed circuit board,
and a mold part on the LED.

3. The backlight unit as claimed in claim 1, wherein the reflective sheet
reflects light emitted from the LED in an upward direction.

4. The backlight unit as claimed in claim 1, wherein the reflective sheet
has reflectivity substantially identical to that of the guide pin.

5. The backlight unit as claimed in claim 1, wherein the reflective sheet
comprises a stepped portion such that a protrusion of the fixing part is
accommodated to the stepped portion.

6. The backlight unit as claimed in claim 1, wherein the reflective sheet
comprises a recess such that a protrusion of the fixing part is
accommodated to the recess.

7. The backlight unit as claimed in claim 1, wherein the LED module
comprises at least three LED disposed with at least one column and two
rows.

8. A display device comprising:a backlight unit comprising an LED module
comprising an LED, a case supporting the LED module, a fixing part fixing
the LED module to the case, a reflective sheet comprising an opening for
exposing the LED on the LED module and the fixing part, and a guide pin
fixing the reflective sheet to the case; anda display unit displaying an
image.

10. The display device as claimed in claim 8, wherein the reflective sheet
comprises a stepped portion such that a protrusion of the fixing part is
accommodated to the stepped portion.

11. The display device as claimed in claim 8, wherein the reflective sheet
comprises a recess such that a protrusion of the fixing part is
accommodated to the recess.

12. A backlight unit comprising:an LED module comprising an LED;a case
supporting the LED module;a first reflective sheet comprising an opening
for exposing the LED on the LED module;a fixing part fixing the LED
module and the first reflective sheet to the case;a second reflective
sheet on the fixing part; anda guide pin fixing the second reflective
sheet to the case.

13. The backlight unit as claimed in claim 12, wherein the LED module
comprises a printed circuit board, the LED on the printed circuit board,
and a mold part on the LED.

14. The backlight unit as claimed in claim 12, wherein the first and
second reflective sheets reflect light emitted from the LED in an upward
direction.

15. The backlight unit as claimed in claim 12, wherein the second
reflective sheet comprises a stepped portion such that a protrusion of
the fixing part is accommodated to the stepped portion.

16. The backlight unit as claimed in claim 12, wherein the second
reflective sheet comprises a recess such that a protrusion of the fixing
part is accommodated to the recess.

17. The backlight unit as claimed in claim 12, wherein the first and
second reflective sheets have reflectivity substantially identical to
that of the guide pin.

18. The backlight unit as claimed in claim 12, wherein the second
reflective sheet has a thickness smaller than that of the first
reflective sheet.

19. The backlight unit as claimed in claim 12, wherein the LED module
comprises at least three LED disposed with at least one column and two
rows.

20. The backlight unit as claimed in claim 12, wherein the second
reflective sheet is formed with the same columns or rows of the fixing
part.

Description:

TECHNICAL FIELD

[0001]The embodiment relates to a backlight unit and a display device
having the same.

[0003]As shown in FIG. 1, the conventional backlight unit comprises an LED
module 10, a case 20, a fixing part 30 and a reflective sheet 40.

[0004]The LED module 10 comprises a printed circuit board 11, an LED 13
formed on the printed circuit board 11, and a mold part 15 formed on the
LED 13.

[0005]The reflective sheet 40 reflects light, which is emitted from the
LED 13, in the upward direction. The reflective sheet 40 is formed with
an opening for exposing the LED 13. The reflective sheet 40 has
reflectivity of 98% or more.

[0006]The fixing part 30 fixes the reflective sheet 40 and the LED module
10 to the case 20. The case 20 may be a cover bottom. An upper portion of
the fixing part 30 is exposed on the reflective sheet 40. For instance,
the fixing part 30 comprises a screw. In general, the fixing part 30 has
reflectivity of about 60 to 70%.

[0007]Since there is a difference in reflectivity between the reflective
sheet 40 and the fixing part 30, the conventional backlight unit
represents non-uniform brightness distribution as shown in FIG. 2. FIG. 2
is a view showing a problem of the conventional backlight unit.

[0008]An optical sheet 70, such as a diffusion sheet, can be aligned on
the backlight unit. Since the fixing part 30 has relatively low
reflectivity, brightness of a region where the fixing part 30 is
positioned may be lowered relative to other regions. Thus, a dark line
may occur in the region where the fixing part 30 is positioned, causing
non-uniform brightness distribution.

DISCLOSURE OF INVENTION

Technical Problem

[0009]The embodiment provides a backlight unit and a display device having
the same, capable of improving brightness uniformity.

Technical Solution

[0010]A backlight unit according to the embodiment comprises an LED module
comprising an LED; a case supporting the LED module; a fixing part fixing
the LED module to the case; a reflective sheet comprising an opening for
exposing the LED on the LED module and the fixing part; and a guide pin
fixing the reflective sheet to the case.

[0011]A display device according to the embodiment comprises a backlight
unit comprising an LED module comprising an LED, a case supporting the
LED module, a fixing part fixing the LED module to the case, a reflective
sheet comprising an opening for exposing the LED on the LED module and
the fixing part, and a guide pin fixing the reflective sheet to the case;
and a display unit displaying an image.

[0012]A backlight unit according to the embodiment comprises an LED module
comprising an LED; a case supporting the LED module; a first reflective
sheet comprising an opening for exposing the LED on the LED module; a
fixing part fixing the LED module and the first reflective sheet to the
case; a second reflective sheet on the fixing part; and a guide pin
fixing the second reflective sheet to the case.

ADVANTAGEOUS EFFECTS

[0013]The backlight unit and the display device having the same according
to the embodiment can improve brightness uniformity.

[0015]FIG. 2 is a view showing a problem of a conventional backlight unit;

[0016]FIG. 3 is a view schematically showing a backlight unit according an
embodiment;

[0017]FIG. 4 is a view schematically showing a backlight unit according
another embodiment; and

[0018]FIG. 5 is a view showing a stack structure of first and second
reflective sheets shown in FIG. 4.

MODE FOR THE INVENTION

[0019]In the description of the embodiments, it will be understood that
when a layer (or film), a region, a pattern, or a structure is referred
to as being "on" or "under" another substrate, another layer (or film),
another region, another pad, or another pattern, it can be "directly" or
"indirectly" on/under the other substrate, layer (or film), region, pad,
or pattern.

[0020]Hereinafter, the embodiments will be described with reference to
accompanying drawings.

[0021]FIG. 3 is a view schematically showing a backlight unit according an
embodiment.

[0022]As shown in FIG. 3, the backlight unit according to the embodiment
comprises an LED module 110, a case 120, a fixing part 130, a reflective
sheet 140, and a guide pin 150.

[0023]The LED module 110 comprises a printed circuit board 111, an LED 113
disposed on the printed circuit board 111, and a mold part 115 formed on
the LED 113. The LED 113 can be mounted on the printed circuit board 111.
The LED module 110 may be formed with at least three LED, and disposed
with at least one column and two rows.

[0024]The case 120 supports the LED module 110. The reflective sheet 140
is formed on the LED module 110 and the fixing part 130. The case 120 may
be a cover bottom.

[0025]The guide pin 150 fixes the reflective sheet 140 to the case 120.
The guide pin 150 can support an optical sheet, such as a diffusion sheet
mounted on the guide pin 150. The guide pin 150 has reflectivity
substantially identical or similar to that of the reflective sheet 140.
The guide pin 150 can be inserted into the case 120 or can extend by
passing through the case 120.

[0026]The reflective sheet 140 reflects light emitted from the LED 113 in
the upward direction. The reflective sheet 140 is formed with an opening
for exposing the LED 113. The reflective sheet 140 represents
reflectivity of 98% or more.

[0027]The fixing part 130 fixes the LED module 110 to the case 120. For
instance, the fixing part 130 comprises a screw and represents
reflectivity of 60 to 70%. The fixing part 130 can be inserted into the
case 120 or can extend by passing through the case 120.

[0028]The fixing part 130 is positioned below the reflective sheet 140.
Thus, the light reflected from the reflective sheet 140 in the upward
direction may have uniform brightness.

[0029]A stepped portion can be formed in a predetermined region of the
reflective sheet 140 in correspondence with the fixing part 130 such that
a protrusion of the fixing part 130 can be inserted into the stepped
portion of the reflective sheet 140. Thus, the reflective sheet 140 may
have a flat upper surface even in the region corresponding to the fixing
part 130.

[0030]In addition, a recess can be formed in a predetermined region of the
reflective sheet 140 in correspondence with the fixing part 130 such that
a protrusion of the fixing part 130 can be inserted into the recess
portion of the reflective sheet 140. Thus, the reflective sheet 140 may
have a flat upper surface even in the region corresponding to the fixing
part 130.

[0031]The backlight unit having the above structure is applicable for
various display devices requiring the light sources. For instance, the
backlight unit can be used for a liquid crystal display device comprising
a liquid crystal panel. The liquid crystal display device displays an
image on a display unit comprising the liquid crystal panel by using the
light provided from the backlight unit. Since the liquid crystal display
device comprises the backlight unit providing the light having uniform
brightness, the liquid crystal display device can display a high-quality
image.

[0032]FIG. 4 is a view schematically showing a backlight unit according
another embodiment, and FIG. 5 is a view showing a stack structure of
first and second reflective sheets shown in FIG. 4.

[0033]As shown in FIGS. 4 and 5, the backlight unit of the embodiment
comprises an LED module 210, a case 220, a fixing part 230, a first
reflective sheet 240, a guide pin 250, and a second reflective sheet 260.

[0034]The LED module 210 comprises a printed circuit board 211, an LED 213
disposed on the printed circuit board 211, and a mold part 215 formed on
the LED 213. The LED 213 can be mounted on the printed circuit board 211.
The LED module 210 may be formed with at least three LED, and disposed
with at least one column and two rows.

[0035]The case 220 supports the LED module 210. The case 220 may be a
cover bottom. The first reflective sheet 240 is formed on the LED module
210 and has an opening for exposing the LED 213.

[0036]The fixing part 230 fixes the first reflective sheet 240 and the LED
module 210 to the case 220. An upper portion of the fixing part 230 is
exposed out of the upper surface of the first reflective sheet 240. For
instance, the fixing part 230 comprises a screw and represents
reflectivity of 60 to 70%. If the fixing part 230 is prepared as a screw,
the upper portion of the fixing part 230 can be prevented from being
exposed out of the upper surface of the first reflective sheet 240 by
increasing fastening force of the fixing part 230. The fixing part 230
can be inserted into the case 220 or can extend by passing through the
case 220.

[0037]The exposed fixing part 230 may cause non-uniform brightness. For
this reason, the second reflective sheet 260 is formed on the fixing part
230. The second reflective sheet 260 may be formed with the same columns
or rows of the fixing part 230.

[0038]The guide pin 250 fixes the second reflective sheet 260 to the case
220. The guide pin 250 can support an optical sheet, such as a diffusion
sheet mounted on the guide pin 250. The guide pin 250 has reflectivity
substantially identical or similar to that of the first and second
reflective sheet 240 and 260.

[0039]The first and second reflective sheets 240 and 260 reflect light
emitted from the LED 213 in the upward direction. The first reflective
sheet 240 is formed with an opening for exposing the LED 213. The first
and second reflective sheets 240 and 260 represent reflectivity of 98% or
more.

[0040]A stepped portion can be formed in a predetermined region of the
second reflective sheet 260 in correspondence with the fixing part 230
such that a protrusion of the fixing part 230 can be inserted into the
stepped portion of the second reflective sheet 260. Thus, the second
reflective sheet 260 may have a flat upper surface even in the region
corresponding to the fixing part 230.

[0041]In addition, a recess can be formed in a predetermined region of the
second reflective sheet 260 in correspondence with the fixing part 230
such that a protrusion of the fixing part 230 can be inserted into the
recess portion of the second reflective sheet 260. Thus, the second
reflective sheet 260 may have a flat upper surface even in the region
corresponding to the fixing part 230.

[0042]The second reflective sheet 260 may have a thickness smaller than
that of the first reflective sheet 240. The brightness distribution by
the second reflective sheet 260 can be improved more than the second
reflective sheet 260 is not exited.

[0043]The backlight unit having the above structure is applicable for
various display devices requiring the light sources. For instance, the
backlight unit can be used for a liquid crystal display device comprising
a liquid crystal panel. The liquid crystal display device displays an
image on a display unit comprising the liquid crystal panel by using the
light provided from the backlight unit. Since the liquid crystal display
device comprises the backlight unit providing the light having uniform
brightness, the liquid crystal display device can display a high-quality
image.

[0044]Any reference in this specification to "one embodiment", "an
embodiment", "example embodiment", etc., means that a particular feature,
structure, or characteristic described in connection with the embodiment
is included in at least one embodiment of the invention. The appearances
of such phrases in various places in the specification are not
necessarily all referring to the same embodiment. Further, when a
particular feature, structure, or characteristic is described in
connection with any embodiment, it is submitted that it is within the
purview of one skilled in the art to effect such feature, structure, or
characteristic in connection with other ones of the embodiments.

[0045]Although embodiments have been described with reference to a number
of illustrative embodiments thereof, it should be understood that
numerous other modifications and embodiments can be devised by those
skilled in the art that will fall within the spirit and scope of the
principles of this disclosure. More particularly, various variations and
modifications are possible in the component parts and/or arrangements of
the subject combination arrangement within the scope of the disclosure,
the drawings and the appended claims. In addition to variations and
modifications in the component parts and/or arrangements, alternative
uses will also be apparent to those skilled in the art.

INDUSTRIAL APPLICABILITY

[0046]The backlight unit and the display device having the same according
to the embodiment can improve brightness uniformity.